>>1847I second this. OP, you need to be more vocal about this to the people you care about. Tell them the same things you've told us. Tell them how alone you feel, or how they never ask how you're doing. Tell them how you feel hurt and want them to have more of a regard toward your emotions, or feel like you're seen as a jester by them. Tell your friends that you feel they're absent from your life. If you can work up the courage to tell us, I think you can tell them as well.
You should stop pretending to be okay to them, and let them know you're
not okay. If these people truly care about your well-being, they'll take some sort of time out of their day to actually listen to you, and try to help you. If they don't care, even after all that, then I'd suggest you find better friends.
I think you need to be a more assertive, OP. Don't be aggressive, because that might alienate someone you care about. But assert yourself. Tell your best friend that you'd like to have a serious discussion, one about how you feel. Tell them how you're hurt by the superficial act you have to put on. Don't tell them that you "don't care" about their relationship, of course, but the superficial act is worth mentioning. Tell them how every day for them is "exciting and emotional", while yours are "completely void of feelings and experiences". Tell them how you "don't want to wear a smile and laugh awkwardly ever again."
I don't know how you feel about this sort of thing, OP, but I'd also recommend seeing a therapist, if you can afford it. Again, tell them everything you've told us. I see a therapist myself, and he's provided so much help and support these past 6 years of my life. Also, I'd recommend getting out of the apartment more. Find something out of the house that you enjoy doing. Something that makes you feel good, and gives your life purpose. Especially if it's something with your friends. In my case, I've taken to volunteering at the local homeless shelter; not only because it gives my life meaning, but because it helps those who need it most.
One more thing; don't listen to all the negatives in this thread trying to bring you down further. They're not worth the time. And, for the record, I'm not trying to "tell" you to do anything, either, OP. I'm just trying to give you some advice. Whether or not you try it is up to you.
TL;DR
Speak up more to your friends about this, try to get out more and do things you enjoy, and see a therapist if you can.